Apparatus supporting an MBMS service

ABSTRACT

Provided is a method and apparatus that may control a configuration and operation of a network including a base station to support a multicast and broadcast multimedia service in a cellular system and may control an operation of a terminal and the like, and thus, may effectively provide a multimedia service in the cellular system.

CROSS-REFERENCES

This application is a reissue application of U.S. Pat. No. 9,025,520issued May 5, 2015, from U.S. application Ser. No. 13/265,917, filedOct. 24, 2011, which is a 35 U.S.C. § 371 filing of InternationalApplication Number PCT/KR2010/002576 which was filed on Apr. 23, 2010,and which claims priority to, and the benefit of, Korean ApplicationNos. 10-2009-0035375, filed on Apr. 23, 2009; 10-2009-0071323, filed onAug. 3, 2009. The contents of the aforementioned applications are herebyincorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a configuration and an operation of anetwork including a base station for supporting a multicast andbroadcast multimedia service in a cellular system, and relates to amethod of controlling an operation of a terminal.

BACKGROUND ART

The present invention may provide a configuration and an operation of anetwork including a base station to support a multimedia broadcastingand multicast service, for example, an Multimedia Broadcast MulticastService (MBMS), in addition to a voice service and a data service in acellular system for providing a packet service, and may provide a methodand a process of controlling an operation of a terminal. The MBMS mayfixably allocate a common channel to provide a service in a conventionalcircuit-based cellular system.

A conventional Third Generation Partnership Project (3GPP)-basedcellular system may apply a code division multiple access (CDMA) scheme,and may provide MBMS using a secondary common control physical channel(S-CCPCH) that reserves and allocates several codes for the MBMS. A 3GPPWideband CDMA (WCDMA) system that is based on an asynchronous mode maysupport an MBMS Single Frequency Network (MBSFN) function, and maycontrol a synchronization of a downlink physical channel and thus, mayimprove a radio link channel through a soft combining function and aselective combining function between multiple routes in the terminal.

The conventional WCDMA system may classify, into various states, thebase station and the terminal for exchanging information such as trafficand the like to apply different operation processes for the informationexchange according to the state of the terminal. The state of theterminal may briefly classified into an idle mode and an active mode,and the active mode is classified into more detailed states such asURA_PCH, CELL_PCH, CELL_FACH, and CELL_DCH to control the operation ofthe terminal. A radio network for providing a service, namely, a servicenetwork, may be constituted by network nodes such as a user equipment(UE), a node B, a radio network controller (RNC), a General Packet RadioService support node (GSN), and the like.

A Long Term Evolution (LTE) system may be a packet-based system, may bea system for providing packet service, and may provide various packetservices, such as a Internet Protocol based voice service, a gameservice, a file Transfer Protocol (FTP) service, a Video streamingservice, a Multicast or Broadcast service, and the like. To perform theabove, the service network is simply constituted by a terminal, a basestation or cell, an access Gateway (aGW) that is an end point of thenetwork, and the like, and the state of the base station and theterminal is simply classified into two states, such as RRC_IDLE andRRC_CONNECTED. The LTE system may adopt an Orthogonal Frequency DivisionMultiple (Access) (OFDM(A)) as a multiple access scheme, and thus, aradio resource allocation is switched into a two-dimensional (2D)allocation based on a frequency and time, as opposed to a codeallocation.

Accordingly, the LTE system may use a method of effectively providingthe Multicast or Broadcast Service by applying a various base stationenvironments including a hierarchical cell format, a controlling methodbased on an operation of a terminal, and a scheme of generating andtransmitting of control information that allocates variable radioresources.

DISCLOSURE OF INVENTION Technical Goals

An aspect of the present invention effectively provides a multicast anda multimedia service in a cellular system.

Technical Solutions

According to an aspect of an exemplary embodiment, there is provided aterminal, and the terminal includes a control information receiving unitto receive information associated with multicast resource allocationfrom a base station, and to receive multicast control information basedon the information associated with the multicast resource allocation,and a receiving unit to receive multicast data from the base stationbased on the multicast control information.

According to another aspect of an exemplary embodiment, there isprovided a base station, and the base station includes a controlinformation transmitting unit to transmit, to a terminal, informationassociated with multicast resource allocation, and to transmit, to theterminal, multicast control information based on the informationassociated with the multicast resource allocation, and a datatransmitting unit to transmit multicast data to the terminal based onthe multicast control information.

According to still another aspect of an exemplary embodiment, there isprovided a terminal, and the terminal includes a control informationreceiving unit to receive control information associated with multicastdata from a base station, a controller to determine, based on thecontrol information, a time duration where the multicast data istransmitted in the data frame, a transmitting unit to transmit, based onthe control information, a join request message with respect to themulticast data to the base station, and a receiving unit to receivemulticast data that the base station multicasts during the time durationin response to the join request message.

Effect

According to the present invention, a multicast and multimedia broadcastservice may be effectively supported in a cellular system.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a configuration of a cellular system providing amultimedia broadcast and multicast service;

FIG. 2 is a diagram illustrating a cellular base station environment tosupport an MBMS;

FIG. 3 is a diagram illustrating each operation of a method ofsupporting an MBMS;

FIG. 4 is a diagram illustrating a structure of a data frame accordingto an embodiment of the present invention;

FIG. 5 is a diagram illustrating a structure of a data frame accordingto another embodiment of the present invention;

FIG. 6 is a block diagram illustrating a configuration of a terminalaccording to an embodiment of the present invention;

FIG. 7 is a block diagram illustrating a configuration of a base stationaccording to an embodiment of the present invention; and

FIG. 8 is a block diagram illustrating a configuration of a terminalaccording to another embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Reference will now be made in detail to embodiments of the presentinvention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to the like elementsthroughout. The embodiments are described below in order to explain thepresent invention by referring to the figures.

FIG. 1 illustrates a configuration of a cellular system providing amultimedia broadcast and multicast service. The multimedia broadcast andmulticast service (hereinafter MBMS) may be configured in a radionetwork composing the cellular system as illustrated in FIG. 1. Basestations 160, 170, and 180 may access an Evolved Packet Core (EPC)network 110 that is a network of a packet-based cellular system. Thebase stations 160, 170, and 180 may access the EPC network through anaccess gateway (aGW) 120. Terminals 161, 162, 171, 172, 181, 182, and183 may access a cellular network via the base stations 160, 170, and180.

The terminals 161, 162, 171, 172, 181, 182, and 183 may access an MBMSGW 130 via the base stations 160, 170, and 180. The MBMS GW 130 is agateway to provide an MBMS.

According to an embodiment, a controlling function to support the MBMSmay be placed in the aGW 120 or the base stations 160, 170, and 180.According to another embodiment, the controlling function to support theMBMS may be placed in an MBMS controlling apparatus 150 that isconnected to the EPC network 110 via a separate interface. According tostill another embodiment, the controlling function to support the MBMSmay be scattered to be placed in aGWs 120 and 140, and the base stations160, 170, and 180.

The MBMS controlling apparatus 150 to support the MBMS may manage thecontrolling function for supporting an MBMS data traffic and service,and may manage a radio resource allocating and scheduling function withrespect to the base stations 160, 170, and 180 that join an MBSFNoperation. Accordingly, the base stations 160, 170, and 180 maydetermine a modulation and coding level for MBSFN transmission accordingto controlling of an MBMS control function.

FIG. 2 illustrates a cellular base station environment to support anMBMS.

A cellular system may transmit an MBMS based on a hierarchical basestation environment. The MBMS may be supported. In the cellular system,a base station may be classified into an MBMS-dedicated base station, acombination service base station supporting both the MBMS and a unicastservice, a general base station that does not support the MBMS, and thelike.

An OFDM or OFDMA-based cellular system may perform an MBMS singleFrequency Network (MBSFN) operation for the MBMS to improve performancewith respect to terminals in a cell boundary area. The MBSFN operationmay be a method where a plurality of base stations overcomesdeterioration in a performance due to a wireless environment, such asinterference and the like, to effectively provide the MBMS to terminalsin the cell boundary area.

To perform the MBSFN operation, base stations included in the same MBSFNarea may transmit the same MBMS information in the same modulation andcoding level based on a predetermined transmission frequency band orcarrier during a predetermined scheduling period or a transmission time.Terminals in the MBSFN area may receive packet information for the MBMSfrom a plurality of cells, may obtain a diversity gain, and may satisfya desired service quality of the system, and thus, may receive the MBMSeven in a poor radio channel environment.

According to another embodiment, a single base station may provide theMBMS, which is referred to as a single cell transmission. In this case,a terminal located in an area of a predetermined base station mayreceive an MBMS only from the corresponding base station. Therefore, areception performance in a cell boundary area may be deteriorated. Inthis case, the base station supporting the MBMS may prevent aperformance deterioration through a repetitive transmission or aseparate modulation and coding scheme.

FIG. 2 illustrates a hierarchical base station environment forsupporting the MBMS. All base stations 220 and 240 in a second layer maybe MBMS-dedicated base stations. Base stations 210, 211, 212, 213, 230,231, 232, and 233 in a first layer may be composed of MBMS base stationsin an MBSFN mode, single cell MBMS transmission base stations, andgeneral base stations, and the like. The general base station may onlyprovide a unicast service.

The base stations 220 and 240 in the second layer may constitute theMBSFN area, or the base stations 220 and 240 in the second layer mayprovide the MBMS to a broad area using only their MBMS-dedicated basestations.

Service areas of the MBMS-dedicated base stations 220 and 240 in thesecond layer may overlap with service areas of the base stations 210,211, 212, 213, 230, 231, 232, and 233 in the first layer. Therefore,terminals corresponding to the base stations 210, 211, 212, 213, 230,231, 232, and 233 in the first layer may receive transmission signalsfrom the base stations 210, 211, 212, 213, 230, 231, 232, and 233 in thefirst layer and the base stations 220 and 240 in the second layer.

Depending on a capability of a terminal, the terminal may receive atransmission signal from a base station in a predetermined layer or mayreceive transmission signals from base stations in a plurality oflayers. Therefore, a unicast or MBMS receiving method and procedure maybe different depending on the capability of the terminal.

An area different from the MBSFN area may exist in the first layer. Inthe area different from the MBSFN, the MBMS may be provided only using asingle base station, which is referred to as a single cell MBMStransmission. A service area of the base station performing the singlecell MBMS transmission may or may not be overlapped with the servicearea of the MBMS-dedicated base station in the second layer.

According to another embodiment, the base stations in the first layermay constitute a first MBSFN area, and the base stations in the secondlayer may constitute a second MBSFN area. In this case, the first MBSFNarea and the second MBSFN area may be overlapped with each other. Thebase stations in the second layer and the base stations in the firstlayer may constitute the same MBSFN area for the MBMS or may share orredundantly allocate a portion of a radio resource for the MBMS, tomaintain a service continuity. The radio resource for the MBMS of anMBSFN mode may indicate a radio resource allocation area that isdistinguished by a packet transmission time, such as a sub-frame on atime axis and the like, and a radio resource allocation area thatdistinguishes a transmission frequency, such as a sub-carrier on afrequency axis, a component carrier, a frequency band, and the like.

To receive the MBMS in the base station environment, the terminal mayreceive control information associated with the MBMS from the basestation. Examples of the control information used for the MBMS may be asfollows.

-   -   1. MBSFN frame and sub-frame allocation and configuration        information    -   2. MBMS notification and indication information        -   1) MBMS indicator to indicate whether MBMS is provided        -   2) Information associated with MBSFN operation and change of            MBMS Control Channel (MCCH)    -   3. MCCH configuration and scheduling information        -   1) MBMS service identifier and MBMS session identifier        -   2) Channel mapping information        -   3) Control information based on terminal operation state        -   4) Information associated with MBSFN    -   4. Information associated with a change of MCCH        -   1) MCCH changing and repetition period        -   2) MBMS start point or reference point        -   3) MBMS session identifier    -   5. MBMS information    -   6. Information associated with MBMS of adjacent cell        -   1) Information associated with adjacent cell in the same            MBSFN        -   2) Information associated with different MBSFN    -   7. Type or form of provided service        -   1) Multicast and broadcast service (e.g., Multicast service,            Broadcast service)        -   2) Information associated with whether joining and release            procedure is required

In an LTE system of 3GPP, the base station may transmit, to theterminal, system information including environment and configurationinformation of the base station. The base station may transmit oneportion of the system information using a broadcasting channel (BCH),and may transmit other portion of the system information using adownlink-shared channel to the terminal.

The base station may transmit one portion of the system informationusing a fixed transmission time and frequency resources and a predefinedmodulation and coding level through the BCH. According to anotherembodiment, the base station may transmit one portion of the systeminformation according to a system information block (SIB) composingother portion of the system information at a predetermined transmissiontime. According to another embodiment, the base station may performCyclic Redundancy Check (CRC) masking of control information, forexample, Physical Downlink Control Channel (PDCCH), with a separatescheduling identifier, for example, a System Information Radio NetworkTemporary Identifier (SI-RNTI), using dynamic allocation to transmit theCRC masked-control information, and may perform addressing radioresource allocation of the corresponding system information to transmitthe radio resource allocation information.

The MBMS notification and indication information may include informationassociated with whether the corresponding base station provides an MBMS,information associated with an MBSFN operation, and the like, and mayinclude information associated with a change of MCCH. The informationassociated with the change of MCCH may include a changing period ofMCCH, a repetition period, a MBMS start point or reference point ofMBMS, an MBMS identifier, an MBMS session identifier, and the like.According to an embodiment, the base station may configure theinformation associated with the change of MCCH separately from the MBMSnotification and indication information. The information associated withthe change of MCCH may only indicate a change of MCCH information, andthe MBMS notification and identification information may configure aseparate control message using only information associated withconfiguration of MBMS and transmission, such as radio resourceallocation information associated with transmission, such as aconfiguration of MBMS and a radio resource allocation, and may transmitthe control message.

According to an embodiment, the base station may not operate a separatenotification or indication information to report the change of MCCH orthe MBMS. In this case, the base station may set a changing period forthe change of MCCH or may set a changing period for changing orcorrecting the MBMS. The base station may separate the changed MCCHinformation and the MCCH information that is not changed for eachchanging period to perform transmission. When the base station transmitsthe changed MCCH information together with the MCCH information that isnot changed, the base station may separately transmit the changed MCCHinformation and the MCCH information that is not changed to enable theterminal to distinctively receive each of the information.

According to an embodiment, when the changing period set by the basestation is greater than a 10-bit system frame number (SFN) defined bythe system, the base station may enlarge the changing period using theSFN. The base station may express the changing period based on a ‘modulooperation’ using a separate identifier or based on a method ofexpressing the changing period as a multiple of an MBMS schedulingperiod.

According to another embodiment, a plurality of base stations includedin an arbitrary MBSFN area or an arbitrary MBMS area may set the samechanging period. In this case, the plurality of base stations may setthe changing period using an identifier, such as an MBSFN frequencydiscriminator, a PLMN identifier, and the like, that may be shared by aplurality of base stations. According to an embodiment, base stationsmay set the changing period to be a multiple of an MBMS schedulingperiod.

According to another embodiment, each of base stations may set adifferent changing periods from each other. In this case, each of thebase stations may set the changing period based on a physical cellidentifier (PCI) or a base station unique identifier (cell ID). Each ofthe base stations may define a separate changing period frame offset toset the changing period. In this case, each of the base stations may usea multiple of an MBMS scheduling period and the changing period frameoffset to express the changing period.

The MCCH control channel configuration and scheduling information mayinclude control information associated with the MBMS. The controlinformation associated with the MBMS may be transmitted from an MBMScontrolling apparatus 150 outside the EPC network 110 of FIG. 1 or fromthe aGW 120. The control information associated with the MBMS mayinclude at least one among information based on setting of a basestation and scheduling information, the information based on the settingof the base station including channel mapping information for MCCHtransmission, control information based on terminal operation state,MBSFN identifier information for an MBSFN operation or MBMS base stationgroup identifier information, MBSFN area indication information or MBSFNboundary cell indication information, multi-antenna configurationinformation such as Multi Input Multi Output (MIMO), diversity, and thelike, information associated with whether a layered coding transmissionis supported, and the scheduling information including radio resourceallocation information for MCCH transmission, MBMS service identifier orMBMS session identifier, radio bearer information, physical channelsetting information for MBMS transmission, and the like.

The MBMS information may include, as information associated with MBMSdata transmission, an MBMS service identifier, an MBMS sessionidentifier, a data packet transmission duration and period, informationassociated with repetitive transmission, and the like.

The information associated with an MBMS of an adjacent cell may beinformation associated with a serving base station that a terminalaccesses or a base station in which the terminal is camping, may beinformation associated with another adjacent base station or adjacentMBSFN area that is different from the serving base station and the basestation in which the terminal is camping, and may include informationassociated with whether MBMS is provided and control informationassociated with the MBMS of a base station that provides an MBMS amongother base stations included in different layers or the same layer wherethe serving base station, the base station in which the terminal iscamping, and the adjacent base station, are included in. The informationassociated with the MBMS of the adjacent cell may include informationassociated with whether the MBMS is provided, information associatedwith MBSFN operation, information associated with a change of MCCHinformation, MCCH control channel configuration and schedulinginformation, and the like.

The information associated with whether the MBMS is provided may includeinformation associated with whether the adjacent base station providesthe MBMS, may include information associated with whether an arbitraryMBMS service is provided or may include MBMS service identifierinformation, for example, a service ID or a session ID.

The information associated with the MBSFN operation may includeinformation associated with whether the adjacent base station supportsthe MBSFN mode, an MBSFN area identifier of when the MBSFN mode issupported, radio resource allocation information for transmission of theMBSFN, for example, information identifying an MBSFN transmissionsub-frame, a sub-carrier, or component carrier.

The MCCH control channel configuration and scheduling information mayinclude a changing period of MCCH information of the adjacent basestation or the MBSFN area, a transmission sub-frame, radio resourceallocation of MCCH, the radio resource allocation being used for aterminal to successfully receive the MCCH information, modulation andcoding information, and the like.

A type or form information of a provided service may include joining andrelease information based on a form of the service in addition toinformation associated with whether the MBMS is in a form of a broadcastor in a form of a multicast.

FIG. 3 illustrates each operation of a method of supporting an MBMS.

In operation S330, a base station 320 transmits system information to aterminal 310 located in a coverage of the base station 320 using abroadcast channel that covers a total base station service area. Thesystem information may include MCCH information and MBMS resourceallocation pattern (MRAP) information. Here, the MCCH information mayinclude radio resource allocation information that transmits an MCCH,and modulation and coding information associated with the MCCH. The MRAPinformation may be allocation information of the sub-frame which iscommonly used by an arbitrary base station and base stations in an MBSFNarea for transmission of the MBMS.

According to an embodiment, the base station may generate the MCCHinformation and the MRAP information. The base station may allocate aradio resource to support the MBMS, and generate information associatedwith the allocated radio resource to be in a form of a pattern togenerate the information associated with the allocated radio resource asthe MRAP information.

According to another embodiment, the aGW 120 or the MBMS controllingapparatus 150 of FIG. 1 may generate the MCCH information and the MRAPinformation, and the base station 320 may receive the MCCH informationand the MRAP information from the aGW 120 or the MBMS controllingapparatus 150. In this case, the aGW 120 or the MBMS controllingapparatus 150 may generate the MCCH information or the MRAP informationbased on adjacent base stations or base stations included in the sameMBSFN area. The aGW 120 or the MBMS controlling apparatus 150 may regardthe adjacent base stations or the base stations in the same MBSFN areaas an arbitrary group unit and may generate the MCCH information or theMRAP information based on the arbitrary group unit in a range where theaGW 120 or the MBMS controlling apparatus 150 is not closely connectedto an MBSFN operation and does not affect on an MBSFN of MBMS datainformation, based on environment of base stations providing the MBMS.

According to an embodiment, the MRAP information may include an MBSFNframe and sub-frame allocation and configuration information. The MRAPinformation may include sub-carrier allocation information in a systembandwidth that is allocated by the base station to transmit MBMSinformation, control information, and the like, MBMS transmission radioframe information, and sub-frame information allocated in an MBMStransmission radio frame to transmit MBMS information.

According to an embodiment, information included in the MCCH informationmay be as follows.

-   -   1. MCCH transmission radio resource location information    -   2. Modulation and coding information for MCCH transmission    -   3. Information associated with change of MCCH        -   1) Start point of change of MCCH        -   2) MCCH changing period        -   3) MCCH repetition start point        -   4) MCCH repetition period        -   5) MCCH information transmission start point

According to an embodiment, the MCCH transmission radio resourcelocation information may indicate information associated with apredetermined frame or a predetermine sub-frame that transmits the MCCHamong MRAP information. The information associated with thepredetermined frame or the predetermined sub-frame that transmits theMCCH may be generated in a form of a pattern to be the MRAP information.

The modulation and coding information for transmission of the MCCH maybe modulation and coding information with respect to an MCCH transmittedusing an MCCH transmission radio resource.

The information associated with the change of the MCCH may include thestart point of the change of MCCH, the MCCH changing period, the MCCHrepetition start point, the MCCH repetition period, and the MCCHinformation transmission start point. The information associated withthe change of the MCCH may be transmitted using a broadcast channel orusing a system information block (SIB1), a system information block 2(SIB2), and the like in 3GPP system information. Specifically, the basestation 320 may transmit, to the terminal 310, the informationassociated with the change of the MCCH, using a pre-reservedtransmission interval or time and a frequency resource and a predefinedmodulation and coding level.

When the base station 320 does not transmit information associated withthe change of the MCCH and physical layer information to demodulate anddecode MCCH information through system information, the base station 320may transmit, to the terminal 310, separate scheduling information for aradio resource that transmits the MCCH. Specifically, the base station320 may reserve and allocate a separate scheduling identifier used forthe MBMS, for example, MBMS-Radio Network Temporary Identifier(MBMS-RNTI), used for transmission of MBMS information and physicallayer control information, for example, PDCCH.

The base station 320 may transmit, to the terminal, informationassociated with a sub-frame that transmits the MCCH and an MBMS TrafficChannel (MTCH).

According to an embodiment, the base station 320 may transmit sub-frameallocation information using a single MSAP without separating the MCCHand the MTCH. The base station 320 may include MTCH receptioninformation in the MCCH and may transmit the MCCH including the MTCHreception information to enable the terminal 310 to receive the MTCHthrough the MCCH.

According to another embodiment, the base station 320 may separate theMCCH from the MTCH and may transmit the sub-frame allocation informationusing each of their MSAPs.

As a first example, the base station 320 may designate a plurality oftransport channels that transmit the MTCH using a single MSAP.

As a second example, the base station 320 may designate a separate MSAPfor each transport channel that transmits the MTCH. In this case, thebase station 320 may separate each transport channel that transmits theMTCH based on a form of a service or a quality of service (QoS), and mayset the separate MSAP that transmits each transport channel.

When the base station 320 is included in a plurality of MBSFN areas, thebase station 320 may report, to the terminal 310, that the base station320 is included in the plurality of MBSFN areas to support each of theplurality of MBSFN areas, using system information or separate physicalchannel information. In this case, the base station 320 may separateMSAP information that transmits the MCCH for each MBSFN area to transmitthe MSAP information, or may designate a sub-frame used for apredetermined MBMS using the same MSAP and may arrange MCCH for theplurality of MBSFN areas in the designated sub-frame to transmit thedesignated sub-frame.

When the MCCH for the plurality of MBSFN areas is transmitted using thesame MSAP, the base station 320 may transmit each MCCH using a separatecoded block or using a single unified block. The base station 320 maytransmit each MCCH using a different MCCH transmission start point, adifferent changing period, and a different repetition period.

The base station 320 may transmit a portion of MBMS control informationto the terminal 310 using the MTCH.

In operation S340, the terminal 310 receives MCCH using the MCCHinformation. The terminal 310 may access MBMS radio resource thattransmits the MCCH, and may receive the MCCH using radio resourcelocation information and modulation and coding information with respectto the MCCH.

The terminal 310 may access the radio resource that transmits the MCCHbased on the physical layer control information using the schedulingidentifier used for the MBMS allocated separately from the systeminformation.

When a form of the MBMS service provided by the base station 320 demandsa separate joining and release procedure, in operation S350, theterminal 310 transmits an MBMS reception request message to the basestation 320. The MBMS reception request message may include a joiningrequest of the terminal 310 with respect to the MBMS service provided bythe base station 320. In operation S360, the terminal 310 receives theMTCH from the base station 320 in response to the MBMS reception requestmessage. The MTCH may include MBMS data. When transmitting of the MBMSdata is completed, the terminal 310 transmits the MBMS reception releasemessage to the base station 320 in operation S370.

When a form of the MBMS service provided by the base station 320 doesnot demand a separate joining and release procedure, the terminal 310may receive the MTCH from the base station 320 in operation S360,without transmitting the MBMS reception request message.

According to an embodiment, in operation S360, the base station 320performs mapping of the MTCH and the MCCH on the same radio resource totransmit the MTCH and the MCCH to the terminal 310. In this case, thebase station 320 may mark an MAC header or a separate field parameter onscheduling information, for example, a channel identifier, fortransmission of the MBMS, to enable data and control information to beseparated in an MAC layer of the terminal 310.

In a case of the MBSFN operation, to multiplex at least one MBMS datapacket information into the same radio resources, a multiplexing processmay be performed in an MBMS user plane (UP) of an MBMS GW that controlsthe base station 320 or a multiplexing process may be performed in apacket data convergence protocol (PDCP) layer when the PDCP layer isintroduced. In the case of the MBSFN operation, a terminal that receivesMBMS information transmitted from a plurality of base stations may needto recognize the MBMS information as being transmitted from a singletransmitter, as opposed to being transmitted from the plurality of basestations.

FIG. 4 illustrates a structure of a data frame according to anembodiment of the present invention.

According to an embodiment, an MBMS may be provided by an MBMS-dedicatedbase station managing a dedicated carrier only for the MBMS andcombination base stations providing the MBMS and a unicast service in asingle cell.

A structure of a frame or a sub-frame for the MBMS in combination cellsmay be different based on whether a physical layer control channel forthe unicast service is utilized.

The frame 410 may be classified, based on MRAP information, into MBMSframes 411, 413, and 415 transmitting MBMS information and unicastframes 412 and 414 transmitting unicast information.

The MBMS frames 411, 413, and 415 may include unicast sub-frames 421,423, 425 transmitting unicast data and MBMS sub-frames 422 and 424transmitting MBMS data.

Each of the MBMS sub-frames 422 and 424 and the unicast sub-frames 421,423, and 425 may include a cyclic prefix (CP). The CP may be constitutedbased on a symbol unit to correct a delay spread occurring in a radiochannel, and a length of the CP may be different based on a coverage ofa base station. Therefore, lengths of CPs of the unicast sub-frames 421,423, and 425 which are only based on a predetermined base station may bedifferent from lengths of CPs of the MBMS sub-frames 422 and 424 whichare based on an MBSFN function.

During a time duration where an MBMS sub-frame is transmitted, terminalsthat receive a unicast service may measure a predetermined parameter ormay estimate a state of a downlink based on a reference symbol. In theMBMS sub-frame, the physical layer control channel 430, for example,PDCCH, transmitting physical layer control information may include a CPhaving the same length as a unicast sub-frame. Therefore, adiscontinuous interval 431 may occur between the physical layer controlchannel 430 and MBMS transmission physical channel 440 in the MBMSsub-frame.

The MBMS transmission physical channel 440 may include MCCH schedulinginformation 441, MTCH scheduling information 442, MCCH 450, and MTCH460. In this case, the MTCH scheduling information 441 may indicatelocation information and radio resource allocation with respect to eachMBMS channel (MCH) that transmits the MBMS and modulation and codinginformation.

When the base station does not transmit the MCCH radio resource locationinformation and the modulation and coding information through systeminformation, the base station may transmit, to the terminal, the MCCHradio resource location information and the modulation and codinginformation by including the MCCH radio resource location informationand the modulation and coding information in the MCCH schedulinginformation 441. The terminal may receive the MCCH 450 using the MCCHradio resource location information and the modulation and codinginformation.

The terminal may receive MTCH scheduling information 442 based on thereceived MCCH 450, and may receive MTCH 460 based on the MTCH schedulinginformation 442.

FIG. 5 illustrates a structure of a data frame according to anotherembodiment of the present invention. In FIG. 5, a base station transmitsMCCH radio resource location information and modulation and codinginformation using system information, and an MBMS-dedicated physicalchannel 520 may not include MCCH scheduling information.

A terminal may receive the MCCH radio resource location information andthe modulation and coding information using the system information, andmay receive MCCH 530 using the received MCCH radio resource locationinformation and the modulation coding information. The terminal mayreceive MTCH scheduling information 540 using the MCCH 530, may receiveMTCH 550 using the MTCH scheduling information 540. The terminal mayreceive MTCH scheduling information using a separate indication fieldparameter or resource allocation information, regardless of the MCCH530, and may receive the MTCH 550 using the corresponding MTCHscheduling information. As illustrated in FIG. 4 or 5, transmission maybe performed in an order of the MTCH scheduling information, the MCCHinformation, and the MTCH.

FIG. 6 illustrates a configuration of a terminal 600 according to anembodiment of the present invention.

The terminal 600 may include a transmitting unit 610, a controlinformation receiving unit 620, and a receiving unit 630.

The control information receiving unit 620 may receive, from a basestation 650, information associated with multicast resource allocation.According to an embodiment, the information associated with themulticast resource allocation may be MCCH scheduling information. Thecontrol information receiving unit 620 may receive multicast controlinformation based on information associated with the multicast resourceallocation. According to an embodiment, the multicast controlinformation may be transmitted based on an MCCH.

According to an embodiment, the multicast control information mayinclude at least one among information associated with whether the basestation 650 transmits multicast data, information about whether a secondbase station 640 adjacent to the base station 650 transmits multicastdata, and information associated with an MBSFN operation of the basestation 650.

The receiving unit 630 may receive multicast data from the base station650, based on the multicast control information.

According to an embodiment, the control information receiving unit 620or the receiving unit 630 may receive, from the base station 650, dataor information in a form of a data frame. The data frame may includemulticast data or unicast data.

According to an embodiment, each of a data frame including the multicastdata and a data frame including unicast data may include a CP. In thiscase, a length of a first CP included in the data frame including themulticast data may be different from a length of a second CP included inthe data frame including the unicast data.

According to an embodiment, the control information receiving unit 620may receive multicast control information included in the data frame. Inthis case, information associated with the multicast resource allocationmay include information associated with a time where the multicastcontrol information is included in the data frame. The control receivingunit 620 may receive multicast control information based on informationassociated with the multicast resource allocation, and the receivingunit 630 may receive multicast data based on the multicast controlinformation.

According to an embodiment, the multicast data transmitted by the basestation 650 may be applied to a service that demands a joining or arelease. In this case, the transmitting unit 610 may transmit, to thebase station 650, a multicast join message based on the multicastcontrol information, and the receiving unit 630 may receive themulticast data from the base station 650 in response to the multicastjoin message. When receiving of the multicast data is completed, thetransmitting unit 610 may transmit a multicast release message to thebase station 650.

According to an embodiment, the control information receiving unit 620may receive information associated with the multicast resourceallocation or multicast control information included in the systeminformation of the base station 650. According to another embodiment,the control information receiving unit 620 may receive, from the basestation 650, the multicast control information or the informationassociated with the multicast resource allocation using a separatedownlink channel.

FIG. 7 illustrates a configuration of a base station 700 according to anembodiment of the present invention.

The base station 700 may include a control information transmitting unit710, a data transmitting unit 720, and a receiving unit 730.

The control information transmitting unit 710 may transmit, to aterminal 740, information associated with multicast resource allocation.According to an embodiment, the information associated with themulticast resource allocation may be information associated with asub-frame through which an MCCH or an MTCH is transmitted, and may begenerated in a form of a pattern.

The control information transmitting unit 710 may transmit, to theterminal 740, multicast control information based on the informationassociated with the multicast resource allocation. According to anembodiment, the multicast control information may include at least oneamong information associated with whether the base station 700 transmitsmulticast data, information associated with whether a second basestation adjacent to the base station 700 transmits multicast data, andinformation associated with an MBSFN operation of the base station 700.

When a layered cell environment is applied, the second base station maybe included in the same layer of the base station 700 or included in adifferent layer from the base station 700.

According to an embodiment, the control information transmitting unit710 may transmit the multicast control information by including themulticast control information in system information of the base station700. The terminal 740 may receive the multicast control informationincluded in the system information of the base station 700. When themulticast control information included in the system information ismodulated or coded based on a predetermined modulation method or basedon a predetermined coding method, a terminal may easily obtain themulticast control information.

The data transmitting unit 720 may transmit, to the terminal 740, themulticast data based on the multicast control information. The terminal740 may receive the multicast data using the multicast controlinformation.

According to an embodiment, an MBMS provided by the base station 700 maydemand a separate joining or release procedure. In this case, thereceiving unit 730 may receive, from the terminal 740, a multicast joinmessage based on the multicast control information. The datatransmitting unit 720 may transmit, to the terminal 740, the multicastdata based on the multicast join message. When transmitting of themulticast data is completed, the receiving unit 730 may receive, fromthe terminal 740, a multicast release message.

When a form of the MBMS provided by the base station 320 demands aseparate joining and release procedure, the terminal 310 transmits anMBMS reception request message to the base station 320 in operationS350. The MBMS reception request message may include a join request ofthe terminal 310 with respect to the MBMS service provided by the basestation 320. The terminal 310 may receive, from the base station 320, anMTCH in response to the MBMS reception request message in operationS360. When transmitting MBMS data is completed, the terminal 310transmits, to the base station 320, an MBMS reception release message inoperation S370.

When the form of MBMS provided by the base station 320 does not demandthe separate joining and release procedure, the terminal 310 receivesthe MTCH from the base station 320 in operation S360 withouttransmitting the MBMS reception request message.

According to an embodiment, the base station 320 performs mapping of theMTCH and the MCCH on the same radio resource and may transmit the MTCHand the MCCH to the terminal 310. In this case, the base station 320 maymark an MAC header or a separate indication field on schedulinginformation for MBMS transmission to enable data and control informationto be distinguished in an MAC layer of the terminal 310.

According to an embodiment, the control information transmitting unit810 may transmit the multicast control information by including themulticast control information in a data frame. In this case, multicastresource allocation information may include information associated witha time duration where the multicast control information is included inthe data frame. Specifically, the multicast resource allocationinformation includes at least one among information associated with atransmission start point of the multicast control information orinformation associated with a length of a time duration where themulticast control information is transmitted, and information associatedwith a transmission completion point of the multicast controlinformation.

FIG. 8 illustrates a configuration of a terminal according to anotherembodiment of the present invention.

The terminal 800 may include a control information receiving unit 810, acontroller 820, a receiving unit 830, and a transmitting unit 840.

The control information receiving unit 810 may receive controlinformation with respect to multicast data from the base station 850,which may be referred to as multicast control information. According toan embodiment, the multicast control information may be transmittedusing an MCCH. The multicast control information may include informationassociated with a time duration where the multicast data is transmittedin the data frame. Specifically, information associated with atransmission start point of the multicast data, information associatedwith a length of the duration where the multicast data is transmitted,information associated with a transmission completion point of themulticast data, and the like may be used as the multicast controlinformation.

The multicast control information may include information regardingwhether a multicast service provided by the base station 850 is aservice demanding a joining or release procedure or a service that doesnot demand the joining or release procedure.

The controller 820 may determine the time duration where the multicastdata is transmitted in the data frame.

When the multicast service provided by the base station 850 demands thejoining or release procedure, the transmitting unit 840 may transmit, tothe base station 850, a join request message with respect to themulticast data based on the multicast control information.

The base station 850 may enable the terminal 800 to join the multicastservice in response to the join request with respect to the multicastdata. The base station 850 may transmit, to the terminal 800, themulticast data corresponding to the multicast service to which theterminal 800 joins, in response to the join message with respect to themulticast data. The base station 850 may transmit, to the terminal 800,the multicast data during a predetermined time duration, based on themulticast control information.

According to an embodiment, the multicast control information and themulticast data may be included in the same data frame and may betransmitted to the terminal 800.

The receiving unit 830 may receive the multicast data from the basestation 850 during the time duration determined by the controller 820.

When receiving of the multicast data is completed, the transmitting 840may transmit a multicast release message to the base station 850.

A small home base station, a relay node, and the like, in addition to ageneral base station in a conventional mobile cellular system, may beused as the described base station.

Although a few embodiments of the present invention have been shown anddescribed, the present invention is not limited to the describedembodiments. Instead, it would be appreciated by those skilled in theart that changes may be made to these embodiments without departing fromthe principles and spirit of the invention, the scope of which isdefined by the claims and their equivalents.

The invention claimed is:
 1. A method of providing, by a base station, aMultimedia Broadcast Multicast Service (MBMS) to a terminal, the methodcomprising: transmitting, to the terminal, a first message, the firstmessage comprising location information of radio resource used totransmit an MBMS Control Channel (MCCH), and modulation and codinginformation applied to the MCCH, and change information of the MCCH; andtransmitting a Media Access Control (MAC) header comprisingidentification information of the MCCH or identification information ofan MBMS Traffic Channel (MTCH); and transmitting the MCCH to theterminal by using the location information and the modulation and codinginformation, wherein the MCCH comprises control information associatedwith MBMS Traffic Channel (MTCH) the MTCH; and wherein, to identify theMCCH and the MTCH mapped are transmitted within a same sub-frame, aMedia Access Control (MAC) header comprises identification informationof the MCCH and/or identification information of the MTCH.
 2. The methodof claim 1, wherein the change first message comprises information on achange of the MCCH comprises, and the change of the MCCH relates to atleast one of a repetition period of the MCCH, a changing modificationperiod of the MCCH, and a changing change in a frame offset of the MCCH.3. The method of claim 1, further comprising: transmitting, to theterminal, an MCCH change notification notifying that which indicates achange of the MCCH.
 4. The method of claim 1, further comprising:transmitting, to the terminal, an area a first identifier of indicatingan adjacent MBMS Single Frequency Network (MBSFN) area adjacent to anMBSFN area to which the base station belongs.
 5. The method of claim 1,wherein the MCCH and the MTCH are mapped within the same sub-frame andthereby are transmitted to the terminal.
 6. A method of receiving, by aterminal, a Multimedia Broadcast Multicast Service (MBMS), the methodcomprising: monitoring an MBMS Control Channel (MCCH) changenotification notifying a change of the MCCH; receiving, from a basestation, a first message, the first message comprising locationinformation of radio resource used to transmit the MCCH, an MBMS ControlChannel (MCCH) and modulation and coding information applied to theMCCH, and change information of the MCCH; receiving, from the basestation, a Media Access Control (MAC) header comprising identificationinformation of the MCCH or identification information of an MBMS TrafficChannel (MTCH); and receiving the MCCH, from the base station, based onthe location information and the modulation and coding information,wherein the MCCH comprises control information associated with MBMSTraffic Channel (MTCH) the MTCH, and wherein, to identify the MCCH andthe MTCH mapped are transmitted within a same sub-frame, a Media AccessControl (MAC) header comprises identification information of the MCCHand/or identification information of the MTCH.
 7. The method of claim 6,wherein the change the first message comprises information on a changeof the MCCH comprises, and the change of the MCCH relates to at leastone of a repetition period of the MCCH, a changing modification periodof the MCCH, and a changing change in a frame offset of the MCCH.
 8. Themethod of claim 6, further comprising: receiving an area a firstidentifier of indicating an adjacent MBMS Single Frequency Network(MBSFN) area adjacent to an MBSFN area to which the base stationbelongs.
 9. The method of claim 6, wherein the MCCH and the MTCH aremapped within the same sub-frame and thereby are transmitted to theterminal.
 10. A terminal, comprising: a microprocessor; and a memory,wherein the microprocessor, when executing program instructions storedin the memory, is configured to: cause the terminal to receive, from abase station, a first message, the first message comprising informationassociated with multicast resource allocation for multicast controlinformation transmitted on a Multimedia Broadcast Multicast Service(MBMS) Control Channel (MCCH) and modulation and coding informationapplied to the MCCH; cause the terminal to receive the multicast controlinformation, from the base station, based on the information associatedwith the multicast resource allocation and the modulation and codinginformation; and cause the terminal to receive multicast data on an MBMSTraffic Channel (MTCH) from the base station based on the multicastcontrol information, wherein the multicast control information comprisescontrol information for the multicast data, and wherein the MCCH and theMTCH are transmitted within a same sub-frame.
 11. The terminal of claim10, wherein the first message comprises information on a change of theMCCH, and the change of the MCCH relates to at least one of a repetitionperiod of the MCCH, a modification period of the MCCH, and a change in aframe offset of the MCCH.
 12. The terminal of claim 10, wherein themicroprocessor is further configured to cause the terminal to receive,from the base station, an MCCH change notification which indicates achange of the MCCH.
 13. The terminal of claim 10, wherein themicroprocessor is further configured to cause the terminal to receive,from the base station, a first identifier indicating an adjacent MBMSSingle Frequency Network (MBSFN) area adjacent to an MBSFN area to whichthe base station belongs.
 14. The terminal of claim 10, wherein themicroprocessor is further configured to cause the terminal to receive,from the base station, a Media Access Control (MAC) header comprisingidentification information of the MCCH or identification information ofthe MTCH.
 15. A communication device for a terminal, the terminalcomprising: a microprocessor; and a memory, wherein the microprocessor,when executing program instructions stored in the memory, is configuredto: cause the terminal to receive, from a base station, a first message,the first message comprising information associated with multicastresource allocation for multicast control information transmitted on aMultimedia Broadcast Multicast Service (MBMS) Control Channel (MCCH) andmodulation and coding information applied to the MCCH; cause theterminal to receive the multicast control information, from the basestation, based on the information associated with the multicast resourceallocation and the modulation and coding information; and cause theterminal to receive multicast data on an MBMS Traffic Channel (MTCH)from the base station based on the multicast control information,wherein the multicast control information comprises control informationfor the multicast data, and wherein the MCCH and the MTCH aretransmitted within a same sub-frame.
 16. The device of claim 15, whereinthe first message comprises information on a change of the MCCH, and thechange of the MCCH relates to at least one of a repetition period of theMCCH, a modification period of the MCCH, and a change in a frame offsetof the MCCH.
 17. The device of claim 15, wherein the microprocessor isfurther configured to cause the terminal to receive, from the basestation, an MCCH change notification which indicates a change of theMCCH.
 18. The device of claim 15, wherein the microprocessor is furtherconfigured to cause the terminal to receive, from the base station, afirst identifier indicating an adjacent MBMS Single Frequency Network(MBSFN) area adjacent to an MBSFN area to which the base stationbelongs.
 19. The device of claim 15, wherein the microprocessor isfurther configured to cause the terminal to receive, from the basestation, a Media Access Control (MAC) header comprising identificationinformation of the MCCH or identification information of the MTCH.
 20. Acommunication apparatus, comprising: a microprocessor; and a memory,wherein the microprocessor, when executing program instructions storedin the memory, is configured to: cause the apparatus to transmit, to aterminal, a first message, the first message comprising informationassociated with multicast resource allocation for multicast controlinformation received on a Multimedia Broadcast Multicast Service (MBMS)Control Channel (MCCH) and modulation and coding information applied tothe MCCH; and cause the apparatus to transmit the multicast controlinformation, to the terminal, based on the information associated withthe multicast resource allocation and the modulation and codinginformation; and cause the apparatus to transmit multicast data on anMBMS Traffic Channel (MTCH) to the terminal based on the multicastcontrol information, wherein the multicast control information comprisescontrol information for the multicast data; and wherein the MCCH and theMTCH are transmitted within a same sub-frame.
 21. The apparatus of claim20, wherein the first message comprises information on a change of theMCCH, and the change of the MCCH relates to at least one of a repetitionperiod of the MCCH, a modification period of the MCCH, and a change in aframe offset of the MCCH.
 22. The apparatus of claim 20, wherein themicroprocessor is further configured to cause the apparatus to transmit,to the terminal, an MCCH change notification which indicates a change ofthe MCCH.
 23. The apparatus of claim 20, wherein the microprocessor isfurther configured to cause the apparatus to transmit, to the terminal,a first identifier indicating an adjacent MBMS Single Frequency Network(MBSFN) area adjacent to an MBSFN area to which the base stationbelongs.
 24. The apparatus of claim 20, wherein the microprocessor isfurther configured to cause the apparatus to transmit a Media AccessControl (MAC) header comprising identification information of the MCCHor identification information of the MTCH.